Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Allowance for receivables from related parties
Balance at beginning of fiscal period	$ 400	$ 400	$ 400
Charges to costs and expenses	0	0	0
Charges to other accounts	0	0	0
Deductions	30	0	0
Balance at end of fiscal period	370	400	400
Tax valuation allowance
Balance at beginning of fiscal period	156,671	153,301	149,606
Charges to costs and expenses	0	0	0
Charges to other accounts	4,489	3,370	3,695
Deductions	0	0	0
Balance at end of fiscal period	$ 161,160	$ 156,671	$ 153,301